1. Field of the Invention
The present invention generally relates to the field of electrical switch. And more particularly, one embodiment of the invention relates to an electrical switch used in various electronic devices such as portable telephones and digital cameras.
2. General Background
Electrical switches are widely used in various electrical devices. Referring to FIGS. 6-9, the traditional electrical switch comprises a housing 1′, a plurality of stationary contacts 2′ fixed in the housing 1′, a dome 3′ with an arcuate center portion covering a center stationary contacts 231′ and a circular side portion slightly contacting with some peripheral stationary contacts 221′, a handle 4′ disposed onto the dome 3′, and a cover 5′ with a center opening 511′ mounted onto the housing 1′.
The handle 4′ comprises a top operating portion 41′, a lower pressing portion 42′ for pressing the dome 3′, and a middle portion 44′ for connecting the operating portion 41′ and the pressing portion 42′. The middle portion 44′ defines a cylinder-shaped configuration, and it defines a top surface 444′ and a corresponding lower surface 441′. The pressing portion 42′ extends from a center of said lower surface 441′ for pressing the arcuate center portion of the dome 3′. When the arcuate center portion of the dome 3′ is pressed down, the dome 3′ contacts with the center stationary contacts 231′. Therefore, the center stationary contact 231′ connects with the peripheral stationary contacts 221′ through the dome 3′, and corresponding connecting function of the switch is achieved.
However, one problem with this electrical switch is that when the operation portion 41′ is accidentally pressed at one side thereof, the whole handle 4′ will slant to one side, and corresponding outer edge of the lower surface 441′ of the middle portion 44′ will undesirably contact with the dome 3′. The undesirable contact will create undesirable operation sense, which may misguide the operator.
Therefore, an improved electrical switch is desired to overcome the aforementioned deficiencies and inadequacies.